Soldering flux



Patented Oct. 11, 1932 UNITED STATES PATENT OFFICE ALBERT J. SA'U 'KAITIS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR '10 AMERICAN CHEMICAL PAINT COMPANY, OF- AMBLER, PENNSYLVANIA, A CORPORATION OF DELAWARE SOLDERING FLUX No Drawing.

This invention relates to the art of soldering and is directed to a soldering flux, parcan therefore be confined to the desired spot.

Heretofore, however, the liquid flux has been more generally used because of its better fluxing qualities. The objects of this invention are to improve the fluxing qualities of paste type -fluxes; to provide a self cleaning flux; to reduce the costof soldering; to simplify the operation of soldering with paste type flux and to generally improve the art of soldering.

Generally stated the invention consists of "a soldering flux which is an admixture of a continuous phase and a dispersed phase. The continuous phase ma consist solely of an emulsifying agent or it may in addition c'omprise a vehicle; a dispersed phase may in addition comprise a fluxing agent.

The metal etching acid may be almost any mineral acid or any non-oxidizing acid which is adapted to etch the metal being soldered,

such as sulphuric, phoshoric, lactic or the halogen acids. I prefer ydrochloric acid.

, The fluxing agent may be a variety of substances of which abietic acid (rosin), beeswax, and the halides such as tin choride, analine hydrochloride, lithium bromide and zinc chloride, are well known. Of these, zinc chloride, due to its qualities and its commercialavailability, is the most efiective and economical.

The vehicle may be any suitable diluent for the emulsifying agent such as a variety of substances which may include, starch paste; various vegetable, mineral and animal oils, such as castor oil, mineral lubricating oilor whale oil; certain greases, like tallow, lard or petrolatum; waxes, such as paraflin, japan, china, and carnauba. Of all these substances I prefer to use petrolatum because it is inexpensive and produces excellent results.

Certain of the metal etching acids may be used at the same time as the fluxing agent; Thus, when hydrochloric acid, phosphoric fluxing agent per se is present.

The vehicle may also play two parts by also I Application filed December 17,1930. Serial No. 562,991.

acid or lactic acid is used, the fluxing agent per se may be omitted. However, I have noted that better results are obtained if the acting as the fluxing agent, thus, abietic acid, stearic acid and tallow may be used in this way, but I have found in this case also' the quality of my flux is better when the vehicle does not have to act in two capacities.

To make the emulsion of my metal etching acid, I may mix the acid with an emulsifying agent. As lanum produces satisfactory results and is easily obtained, I prefer it.

A suitable emulsion to practice my invention maybe made by admixing:

Lanum 10.710 pounds Hydrochloric acid (20 B.) 1.233 gallons The lanum constitutes the continuous the fluxing agent, which is best introduced as an aqueous solution. When my preferred fluxing agent, zincchloride, is used, I dissolve it in water to make a 70% solution and add 1.028 gallons of it to the above admixture which I incorporated by constant stirring.

Such an admixture has strong fluxing properties but is too stiff for quick manipulation and often does not properly adhere to the surface to be soldered and hence should be diluted with a vehicle. The amount of ver" '7 hicle used depends on personal judgements and requirements; I prefer to dilute" the above admixture with 46.120'pounds'of fpe- "trolatum, to form an admixture of the lowing composition:

Lanum 10.710 pounds Hydrochloric acid (20 B.) 1.233 gallons Zinc chloride (70% solution) 1.028 gallons Petrolatum 16.120 pounds In this composition, the lanum and the petrolatum constitute the continuous base and the zinc chloride and the hydroc or1c acid constitute the dispersed phase.

The amount of each ingredient may be varied over a wide range so lon as this phase' relationship is maintained, ot erwise a se aration of the composition may result to t e great deteriment of its fluxing properties.

My soldering flux is used in the usual manner. It is applied with the finger, a brush, a rod or a swab, to the metal to be soldered. The solder is then applied with the usual heated iron or themetal is heated with a torch or flame and the solder melted on, from a rod or wire.

The advantages of my flux are es clally noticeable where the metal to be sol ered is covered with a thin film of oxide. Heretofore it has been necessary-to remove the film of oxide as a separate operation before applyin the soldering flux; when my flux is used t is pre-cleaning operation ma be dispensed with, as the emulsified acid 1s adapted to dissolve this oxide film, and hence the soldering can be accomplished quicker and with less labor.

I do not intend to be limited in the practice of my invention save as the scope of the prior art and of the attached claims may require- I claim: 1. A soldering flux paste being an admixture of a continuous phase com rising lanum as an emulsifying agent an a dis rsed phase com rising a metal etching aci 2. A soldering flux paste being an admixture of a continuous phase comprlsing lanum and a dis rsed phase comprising a metal etching acid and a fluxing agent.

3. A soldering flux paste being an admixture of a continuous phase comprising lanum and a dispersed phase comprising hydrochloric acid and a fluxing a cut.

4. A soldering flux paste eing an admix ture of a continuous phase comprising lanum and a dispersed phase comprising hydrochloric acid and zinc chloride.

5. A soldering flux paste being an admixture of a continuous phase com rising lanum and a vehicleand a disperses phase comprising a metal etching acid.

6. A soldering flux paste being an admixture of a continuous phase comprising lanum and petrolatum, and adispersed phase comprising a metal etching acid.

- 7. A soldering flux lpaste being an admixture of a continuous p ase comprising lanum and petrolatum and a dispersed phase comprising hydrochloric acid and zinc chloride.

ALBERT J. SAUKAITIS 

